1. Field of the Invention
This invention relates to a machine management system for managing machines existing in a plant and a message server used for the machine management.
2. Description of the Related Art
A machine management system, can manage machines systematically according to a tree structure called a plant hierarchy. It also has a function of displaying the diagnosis result of each machine.
FIG. 1 is a drawing to show a display screen example of a machine management system in a related art.
As shown in FIG. 1, the machines existing in a plant are classified under a multilevel hierarchy and are displayed on a screen as a tree structure. In the figure, an icon “□” represents a plant hierarchy level and an icon “O” represents a machine.
An icon representing the diagnosis result is displayed for each machine on the tree. In the figure, the diagnosis result is displayed as an icon for machines A to H. If the diagnosis result is normal, the icon “O” is displayed; if the diagnosis result is abnormal, a mark “!” is displayed in the icon “O”.
The letter in the icon “□” represents the type of plant hierarchy level. The correspondence between the letters and the plant hierarchy levels is as follows:
S: Site, A: Area, C: Process Cell, U: Unit, E:
Equipment Module
Each machine is assigned to the hierarchy level of Equipment Module on the tree structure of the plant hierarchy. The user can switch between display and non-display modes of subordinate hierarchy levels to each node as desired. The diagnosis result of each machine is displayed in the node of the machine on the tree.
JP-A-2004-29897 discloses a machine management system for managing machines existing in a plant.
However, in the display mode of the related art, the diagnosis result of one machine is displayed only in the node of the machine on the screen. Thus, the user cannot see on the screen that the diagnosis result of a machine at a lower level not displayed on the screen is abnormal.